In this day and age, the benefits of the crowd are commonplace.
Wikipedia is written by volunteers,
and community question answering has received the attention of researchers [1]}, [2]}.
When aggregating information collected from crowds,
it may be important to know whether judgments were collected independently of each other.
If they were not,
crowd psychology [3]}
and the power of persuasion [4]}
can bias individual judgments and eliminate the wisdom of the crowd.
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